Double-action saw-set.



m.- 685,644. Patented Oct. 29, 190:. n. m. noszms & J. H. MABA.

DOUBLE ACTION SAW SET.

(Application filed June 7, 1901.)

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WITNESSES UNITED STATES PATENT OFFICE.

DUANE MORTIMER ROBERTS AND JOSEPH HENRY MARA, OF MARLOW,

INDIAN TERRITORY.

DOUBLE-ACTION SAW-S ET.

SPECIFICATION forming part of Letters Patent No. 685,644, dated October29, 1901. Application filed June '7, 1901. Serial No. 63,5 56. (Nomodel.)

'To all whom it may concern.-

Be it known that we, DUANE MORTIMER ROBERTS and JOSEPH HENRY MARA,citizens of the United States, and residents of Marlow, in the ChickasawNation, Indian Territory, have invented anew and Improved Double-ActionSaw-Set, of which the following is a full, clear, and exact description.

Our invention relates to double-action sawsets, sometimes calledsaw-wrests, and more particularly to the small machines or tools whichare operated by hand for the purpose of bending'the teeth of the saw tothe proper angle. It will be understood, of course, that in every saweither all of the teeth or certain alternate teeth must be bent outwardfrom the imaginary plane passing through the saw-blade, and thisoperation is necessary both in new saws and in those in which throughuse in sawing the teeth have been closed or partially closed by thepressure of the material sawed. Our device also prevents buckling of thesaw, as hereinafter explained.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in all the figures.

Figure 1 represents a side elevation of our saw-set, partly in section,upon the line 1 1 of Fig. 3. Fig. 2 is a somewhat similar view, slightlyenlarged, the handles being represented as broken away. Fig. 3 is a planview, partly in section; and Fig. 4 is a detail in perspective, showingthe setting-punches, together with the manner of their application tothe teeth of the saw.

The entire structure except the handles is made, preferably, of metal.

Two similar blocks 1 2' are each provided longitudinally'with a slot-34, through which a fastening, preferably thumb-screws 5 6, passesloosely and is firmly secured in the opposing block. By loosening bothscrews, sliding one block slightly upon the other, and tightening thescrews the blocks can be adjusted longitudinally upon each other withinblocks are in the position shown in Fig. 3:

Each block is provided with another slot 3' 4', passing entirelythroughout the length of the block and so arranged that when placedtogether said slots will register with each other and form a kerf-likeslot, into which the blade of the saw can be inserted, as shown in Figs.

1, 2, and 3.

Mounted upon each block isa bracket 9 10, upon which the handle-irons 1112, carrying the handles 13 14, are pivoted by means of the pins 15 16.The said handle-irons 11 12 are each provided with a slot 17 18, adaptedto receive the brackets 9 10 and alsovto receive the heads 19 20, whichare pivoted in said slots by means of the pins 21 22. These pins, likethe pins 15 16, may pass entirely through the handle-irons, if desired.Each of the pivoted heads 19 20 is provided with a projection 23 24integral therewith, said parts together constituting a punch. Theprojections 23 24. pass through the respective holes 1 2 in the blocks 12 and, likethe holes, miss each other and stand in a staggering relationwhen the blocks occupy the position shown in Fig. 3. When, however, theblocks 1 2 are moved relatively to each other, the relative position ofthe punches is changed. By this means the punches may be moved towardand from each other within the limit prescribed by the length of theslots 3 4. and may even be adjusted to register with each other, ifdesired.

We find that a good plan is to make the saw-set adjustable to an extentsuitable for handsaws ranging from No. 4. to No. 12, though of coursethe inventionis applicable to any other reasonable range of sizes.

Upon each block is mounted a gage, being preferably an L-shaped bracket25 26, provided with a slot 27 28, through which passes a set-screw 2930, by which the L-shaped part may be adjusted upon the block. This gageis for the purpose of limiting the inward movement of the handles 13 14,and thereby limiting the, thrust of the punches, so that the puncheswill bend the saw-teeth to any predetermined degree and will for thispurpose be controllable by the screws 29 30. The heads 19 20, upon whichthe projections are integrally mounted, are each provided with ashoulder 21' 22, which moves directly against the bracket 25 26 untilstopped thereby. These brackets should of course be of good material,such as steel, as they are subjected to considerable strain.

The method of using our invention is as follows: A saw 3l--say, forinstance, a No. 6 handsaw-is placed with the teeth thereof in thekerf-shaped slots 3 4, the screws 5 6 are loosened ,and the blocks 1 2are adj usted longitudinally by one sliding upon the other until thepunches will be exactly as far apart in the longitudinal direction ofthe blocks as any two successive or alternative teeth of the saw. Theblocks are now clamped to each other by tightening the screws 5 6, thegages or brackets 25 26 are adjusted, as above described, to limit theplunge of the punches, and the handles are alternately gripped andreleased as the blocks (now considered as a body) are moved along thesaw by successive steps of the length of two teeth each. The punches arealways parallel, for the reason that when the blocks are adjusted eachand every part is moved bodily to a position parallel with that which itpreviously occupied.

Among the general advantages presented by our invention is the fact thatin using it no buckling of the saw is likely to occur. In many of thesaw-sets heretofore used the action is such as to distort the blade ofthe saw. In other words, the action of such devices is not entirelylocal. To bend a tooth requires considerable pressure,-and if thispressure be allowed to distribute itself over any part of the blade awayfrom the tooth the saw will buckle. Again, the buckling effect may besomewhat cumulative, so that a slight curvature from each of severalteeth may contribute to produce a permanent distortion of the saw. Inour device the punches each act as an anvil for the other, so that thepressure of either punch has practically no effect except the localelfect in bending a tooth. The kerfshaped guideway by preventing unduemotions of the saw-blade also assists in preventing the saw frombuckling.

Our device is light, simple, cheap, and convenient and can be made uponthe scale shown in the drawings or upon a larger or smaller scale, ifdesired.

Various modifications may suggest themselves as occasion oifers, allbeing within the scope of our invention. I

Having thus described our invention, we

claim as new and desire to secure by Letters ranged blocks may begoverned at will.

2. A saw-set, comprising a central body portion, a plurality of leversoperatively se* cured to the same, punches mounted upon said levers andprovided with shoulders, and adjustable brackets mounted upon said cen*tral body portion for limiting the movements of said shoulders.

3. A saw-set, comprising a central body portion, a plurality of leversoperatively se= cured to the same, punches mounted upon said levers andprovided with shoulders, movable brackets mounted upon said body portion for limiting the movementsof said shoulders and provided withslots, and screws passing through said slots for adjusting saidbrackets.

1. A saw-set, comprising a central body portion, levers pivoted upon thesame,- punches secured to said levers and provided I with shoulders,brackets detachably secured to said central body portion and providedwith anvil-surfaces for engaging said shoul ders, and means foradjusting the position of said brackets relative to said central bodyportion.

5. A saw-set, comprising a body portion made in sections andprovided-with guidingapertures, levers connected with said sections,punches provided with shoulders, loosely mounted upon said levers andextending through said guiding-apertures, and-brackets provided withanvil-surfaces for engaging said shoulders of said punches.

6. A saw-set, comprising a body portion made in sections and providedwith guidingapertures, levers connected with said sections, punchesprovided with shoulders and loosely mounted upon said levers andextending through said guiding-apertures, brackets provided withanvil-surfaces for engaging said shoulders of said punches, andadjustingscrews for securing said brackets in predetermined positions.

7. A saw-set, comprising a central body TIO ' oted upon said bodyportion, and punches loosely mounted upon said levers and passingthrough said apertures for the purpose of maintaining the punches inlines parallel with each other at all times.

In testimony whereof we have signed our names to this specification inthe presence of 15 two subscribing witnesses.

DUANE MORTIMER ROBERTS.

JOSEPH HENRY MARA.

Witnesses:

GEORGE A. FEAGLES,

JOSEPH O. Gems

